New Functionality in COMSOL 4.3

The LiveLink for MATLAB® includes the following new wrapper functions:

  • mphimage2geom: convert image data to geometries.
  • mphevalpoint: evaluate expressions at geometric vertices.
  • mphmean, mphmin, mphmax: evaluate mean, minimum, and maximum of expressions in a data series, respectively.
  • mphevalglobalmatrix: evaluate a global matrix, for instance as for an S-parameter matrix.
  • mphsearch: GUI to search for expression, variables, tags, and so on in a model.

New functionality have also been added to the existing wrapper function, these are listed below:

  • More information on more nodes are now available in mphnavigator. You can also get solution information such as how the solution object and the solution data sets are connected to each other.
  • Selection tags in mpheval and mphint.
  • Extrapolation to evaluate data outside the geometry with mphinterp.
  • Support for contour labels in 2D and 3D with mphplot.

It is now possible to update the MATLAB installation folder directly in the Preferences dialog box from the COMSOL Desktop.

A new method to disable automatic variable update is now available. This can help for performance improvements in large model implementations.

Known Issues

The option to plot on a server by starting a COMSOL server with the option -graphics is not supported on Mac.

Backward Compatibility vs. Version 3.5a

MATLAB Support with COMSOL Multiphysics Version 3.5a

COMSOL makes a effort to be backward compatible: you can load Model MPH-files created in COMSOL Multiphysics 3.5a and later versions in COMSOL Multiphysics 4.3.

When going from version 3.5a to version 4, a major revision was made to the MATLAB interface. This revision was made to reflect changes made to the new user interface and to support parameterized geometry operations. As a result, a new MATLAB interface syntax is used in today’s version 4 of COMSOL Multiphysics and its add-on product LiveLink for MATLAB.

In order to assist in the conversion process, a special compatibility mode was created to facilitate the new syntax. This compatibility mode, together with the LiveLink for MATLAB function mphv4, is no longer supported in COMSOL Multiphysics 4.3.

If you wish to convert a model defined with an M-file created with version 3.5a to the version 4.3 format, we recommend the following procedure:

Run the M-file using COMSOL Multiphysics 3.5a and save the model, using flsave, as an MPH-file.
Load the model into COMSOL Multiphysics 4.3 and verify that the model settings have been translated correctly. In addition, verify that the model can be meshed and solved.
Select File>Reset History.
Select File>Save as Model M-file.

The saved M-file can now be tested if you start COMSOL Multiphysics 4.3 with MATLAB.

If you have any problems with this conversion process, please contact COMSOL’s technical support team at or your local COMSOL representative.


The functionality corresponding to the geometry functions geom2 and geom3 from version 3.5a is not available in version 4.3. This functionality will be available in a later release.


See the section The COMSOL Java API regarding changes in the COMSOL API.